Fig. 7. Oocyte maturation induced by Xp38γ/SAPK3 is independent of Xp42Mpk1 MAPK activation and does not require protein synthesis. (A) Oocytes were injected with Xp38γ/SAPK3 mRNA, incubated overnight and then injected again with 50 ng of MalE-MKK6-DD protein. Some oocytes were either pre-incubated with 50 µM U0126 for 1 h or injected with the MAPK phosphatase Pyst1 and incubated overnight before MKK6-DD injection or progesterone treatment. Oocytes were collected after 12 h and their lysates analysed by immunoblotting using the indicated antibodies, and by H1K assays. The occurrence of GVBD in the different oocyte groups is indicated at the bottom of the panel. (B) Oocytes were injected with Xp38γ/SAPK3 mRNA, and 14 h later were injected with 50 ng of MKK6-DD protein. Some oocytes were incubated with 50 µg/ml CHX for 1 h before MKK6-DD injection. The oocytes were synchronized after white spot (ws) appearance (samples to the right of ws). Oocyte lysates were analysed by immunoblotting using the indicated antibodies. (C) Morphological appearance of the oocytes. Untreated (control) and progesterone-treated oocytes were collected at 7 h; MKK6-DD + Xp38γ-injected oocytes with or without CHX were collected at 4 h.